<h4>传统风格</h4>
<label><input type="checkbox" ng-model="vm.checked"/>&nbsp;复选框</label>
<div>
  {{vm.checked}}
</div>


<h4>按钮风格</h4>
<label ng-class="{active:vm.checked}" class="btn btn-primary"><input type="checkbox" class="hidden"
                                                                     ng-model="vm.checked"/>&nbsp;复选框</label>
<div>
  {{vm.checked}}
</div>
